ST. PETERSBURG, Florida -- Three smokestacks that have been a St. Petersburg landmark for more than 50 years were imploded Tuesday morning.

The P.L. Bartow Steam Power Plant smokestacks, each standing 300 feet tall, were demolished at 10 a.m. The implosion lasted about 10 seconds and brought the stacks down to the side, much like a tree falling.

"Demolition work is inherently very dangerous and explosive demolition is dangerous as well," Progress Energy spokesperson Suzanne Grant told 10 News. "Back in June, the demolition was a different type. This is using explosives. That was a controlled collapse where they were weakening structures and pulling it down. It's really a different thing, but the safety is paramount as always."